Cylinder-reboring tool



Match 4, 1924. 1,485,930

- v. G. HOWIND CYLINDER HEBORING TOOL Filed Feb. 24. 1922 2 Sheets-Sheet 1 Marh 4,, 1924. 1,485,930

V. G. HQWIND CYLINDER REBORING TOOL Filed Feb. 24; 1922 2 Sheets-Sheet 2 liiillllll....@

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Patented Mar. 4, 1924.

PATENT OFFICE.

VICTOR G. HOWIND, 0F NEWPORT, KENTUCKY.

CYLINDER-REBORING TOOL.

Application filed February 24, 1922.

To all 11:71 am it an my concern Be 1t known that I. VIo'roR G. HOWIND, a citizen of the United States, and res ding at Newport, in the county of Campbell and State of Kentucky, have invented a new and useful Imprm'ement in Cylinder-Reboriug Tools. of which the following specification is' a full disclosure.

This invention relates generally to the art of metal boring. and particularly to apparatus and method for re-borin and refinishing engine cylinders, especially of that type of engine used for automobiles.

In re-boring automobile engine cylinders it is desirable that the work be accomplished without removing the engine cylinder block from the automobile chassis, the dismantling consuming considerable time, labor and expense.

My improvement, from a point of utility, may be characterized as a portable appliance for quickly and expeditiously re-boring automobile engine cylinders without removing the engine from its support.

The boring tool is capable of being operated by a portable manually operated fixture, temporarily fixed to the engine block or otherwise secured in position for rotating and feeding the boring tool into a cylinder.

The boring tool is self-centering and selfguiding within the cylinder and this is accomplished in providing a circular disk cutter with a pilot hub or guide at the forward side of approximately the normal diameter of the cylinder, and a follower guide at the rear side of the cutter, of approximately the diameter of the cutter, and in the provision of receptacles at the opposite sides of the cutter, for collecting, and storing the bor- 1n i side from the structural features of my improved re-boringtool, the invention is also directed to a method for re-boring engine cylinders under which the boring tool here-- in disclosed is iery applicable. The method consists in re-boring the cylinder with a circular cutter of minute oversize to the normal diameter of the cylinder, making a skim and a finishing cut, and repeating the performance with bore tools of a gradually increasing proportion until the required reboring diameter is obtained.

An object, therefore, of' this invention is Serial No. 538,934.

to reduce the amount of time and labor incident to an engine cylinder re-boring by the provision of a circular cutter having pilot and follower guides respectively at its opposite sides and in boring the cylinder by a series of successive boring operations, with 'tools of this character, as a set of progressive step increasing size, forgradually and pro 'ressively enlarging the cylinder bore conformably to finishing requirements. Each tool has a universal connection with a driving and feeding fixture.

By the use .of my improved apparatus, it is unnecessary to completely dismantle the power plant, it being suflicient to remove the cylinder head, lower inspection plate, connecting rods and pistons only, thus saving from six totwelve hours time relative to disassembly and re-assembly alone. Moreover, the device is attachable by a screw or screws engaged with the cyhnder-head screw openings, obviating the use, 111 most cases, of special fastening meaiis for the support of the apparatus.

Another object is the provision of means for making possible the boring of both open and closed end cylinders, with the same apparatus, also to bore, from what heretofore have been considered inaccessible positions.

Another object is to prevent the dropping of turnings into the crank-case, to the sub sequent detriment of the bearings.

Other objects and certain advantages will be disclosed in the description of the drawings, forming a part of this specification, and reference is made to said drawings, in which:

Figure 1 is a vertical section, showing the apparatus as used for boring an open end cylinder, and illustrating the universal joint connection of the supporting means with the operating and feed rod.

Figure 2 is a view similar to Fig. 1 but in a plane at right angles thereto.

Figure 3 is a plan of Figure 1.

Figure 4 is a vertical central section of an assembly of guide and cutter elements on line 44 of Fig. 5, illustrating the universal joint connection. coupled to the tool carrier and guide, and to the lower end of the operating and feed rod.

Figure 5 is a view at right angles and similar to Fig. 4, on line 55, Fig. 4.

Figures 6 and 7 are respectively side and end detail views of that element of the universal joint which is pivoted crosswise of the cutter or tool-carrier and guide.

Figures 8 and 9 are respectively plan and side views of the companion element of the joint, shown in Figs. 6 and 7.

Figures 10 and 11 are respectively plan and side views of the coupling element detachably securable to the upper end of the element of Figs. 8 and 9 and to the lower end of the operating and feed rod.

Figure 12 is a plan view of the cutter carrier.

Fig. 13 is a section on line 13-13 of Fig. 12.

Figure 14 is a plan of the guide member. Figure 15. is a section on line 15-15 of Fig. 14.

Figure 16 is a plan view, showing the manner of attaching the cutter or tool to the cutter carrier for use in completin the boring of a closed end cylinder, and s owing the universal joint attached to said outter carrier.

Figure 17 is a section on line 17-17 of Fig. '16.

. Figures 18 and 19 are respectively enlarged detail fragmentary plan and edge views of the cutter or tool.

Figure 20 illustrates the first part of the boring operation, fora' closed end cylinder, and shows how the operation can be performed from below.

Figure 21 shows how the boring operation of Fig. 20 is completed, by ren'ioving the guide member and continuing the operation with the cutter-carrier acting as a guide.

Figure 22 is a diagrammatic view illustrating the step-by-step. increase of the diameter between the members of a series of boring assemblies. The arrows indicate that the guide member of a succeeding assemblyjs equal in diameter to the cutter carrier of the one preceding it.

The boring tool primarily comprises a circular cutter intermediately between and secured to a pair of cutter centering pilot and follower guides, as hubs for the cutter, of relatively difi'erent diameters. The pilot guide hub is positioned in advance of the cutter approximately of the normal diameter ofthe cylinder to be re-bored, rotatable and slidable within the cylinder for initially centering and guiding the cutter in starting a re-boring operation. The follower guide hub is positioned upon the opposite side of the cutter approximately of the diameter of the cutter and free to rotate and slide within "the re-bored portion of the cylinder.

The boring tool as a unit may be rotated and progressively advanced within the cylinder by various forms of power and tool supporting fixtures, but for automobile engine service it is desirable to provide a manually o erable and portable fixture readily attac able to the engine block, with out requiringthe engine block to be removed from the automobile chassis.

A type of portable tool supporting fixture is shown in Figs. 1 and 2 for boring the open end cylinders from the upper end, and referring to said figures:

The cylinder block is shown at 1, and the cylinderto be bored at 2. An L-shaped support 3 is attached to the, block, by a screw 4, traversing an elongated adjustment slot 5 of the support. In most instances this screw is engageable with one of the cylinder head screw openings, thus obviating the necessity of special support-attaching means.

Pivoted at 6 to the upstanding portion of the support 3 is an L-shaped member 7 pro viding a horizontal forked extension between the fingers of which upon the trunnions 8, is pivoted a block or nut 9, providing a screw threaded bore engaged by the feed threads 10, of an operating and feed rod 11, squared at its one end as at 12. for engagement by a suitable square socketed handle, for rotating said rod. The member 7 is further attached at its upper end to the support 3, by a bolt 13, traversing an elongated arcuate slot 14, concentric with the pivot 6, to allow limited rocking movement of said member about said pivot, and this movement in conjunction-with the rocking movement of the block 9, and of a universal connection attached to the lower end of the rod and to the boring tool, allows rotation of the cutter and its guides by the, rod, when the rod and toolaxes are disaligned. v

The universal joint connection between the tool driving and feeding rod, and the means for operating the same, permits of the efiective performance of boring operations, at angles to'the work.

The boring tool comprises three elements, suitably clamped together and combined as a unit, one of the elements beingprovided with a universal joint connection for attachment with the operating and feed rod 11.

One ofthe elements 16, as a follower guide-hub for a circular cutter, may be designated a cylindrical cutter-carrier, and is designed to support a Eircular disk cutter 20, of approximately the diameter of the carrier 16, and referably of the construction herein il ustrated. This cutter is ada ted to be clamped between the "carrier or ibllower guide hub 16 and a pilot guide hub- The follower guide hub 16 is of a within the ,re-bored portion of the given cylinder. The pilot guide element 17, at

matinee tachable to the cutter-carrier 16, in central axial alignment therewith. is approximately of a diameter of the engine cylinder to be bored. or .001 less than the diameter of the engine cylinder. so that it will slide within the engine cylinder. 'lhis hub or guide member 17, precedes the cutter 20. throughout the operation ot'horing an open end cylinder. ln boring a closed end cylinder. however, the boring is partly performed with the pilot guide element l7 attached. The pilot guide is used only in starting and until a sufficient depth of the cylinder has been bored to make the follower guide effective. The pilot guide is only necessary in starting.

The guide member 16. at one end thereof, isprovided with a counterturned tubular boss. having a central opening .16 therethrough. The-boss provides a spindle or mandrel tor the cutter and a support for the pilot guide member l'l. which has an opening ll" through one end thereof. for engagement upon the boss for concentrically uniting the parts and for clamping the cutter between the members l6. 17. The members l6 and 17 each have their cutter abutting end faces respectively provided with an annular recess 22 as pockets. at opposite sides of the cutter. for receiving and collecting the tool borings. Each recess has its outer wall bevelled as at 2. on its inner periphery. for providing a clearing adjacen the side of the cutter leading into the recess. The cutter 20 represents a disk having a toothed periphery engaged about, the boss of the guide member 1 and the tooth depths are of such a degree that the space between the teeth opens into the recesses at the guide member, and relative to the clearance formed by the bevels 23. so that the cuttings or borings are directed into either of said re cesses 2222.

The bevel of the pilot. guide 1? is slightly inwardly spaced from the. outer periphery of the cutter teeth inasmuch as the guide is less diameter than the cutter and follower guide. ll hen boring from above, however. the cuttings will be deposited within the groove 22 of the guide 12 The periphery of the opening 20 i cutter is provided with a notch 25 de l to engage a pin 26 projecting laterally" from the boss 24, for keying the cutter to the fol lower guide.

As shown in Fig. 4, the guides 16 and l7, with the cutter therebetween, are suitablv clamped together by screws 26 engaging with n the gned the boss 24. the heads of the screws over-- lapping and engaging a flange 27 of the guides 17. The driving connection for the tool is made through a universal joint. connected with the guide member 16. consisting of a member or gudgeon 28, attached to the guide member 16. crosswise of the opening 16, by pm 29, engaged into radial bores through the boss of the guide member 16. the central axis of this pin being aligned with the center line A of the cutter 20. the said pin being thus also located centra of the lengthwise dimension of the elements 16 and 17. their lengths being equal. The pin 2!) passes through a pin 29 of larger diameter at right angles thereto and coaxially therewith, this pin 29 acting to pivot the yoke member 30 of the universal joint. to which is attached, by a set screw 31. a square socketed coupling member 32. providing aligned openings 33. said member 32" being attachable to-the rotating andfeed rod 11 by a pin 34 passed through the aligned openings of the coupling and rod.

By means of this universal joint. operating in conjunction with the universal joint of the support 3. the rotating and guide rod 11 may be operated to rotate a boring assemblywhen said rod and assembly are not coaxially aligned. I

Figures 16. 17. 'ZO and 21 illustrate the manner of boring from below a closed upper end cylinder. The first part of the o tion is performed in. a manner identical to that for boring an open end cylinder. thejaclr fixture being modified to suit this condition. In this instance. the jack-fixture comprises a pipe section 35 attached at one end to the coupling member 32 and threaded interiorly, as at 36. at its opposite end for engagement with the threads of a rod 37 held from rotation by a suitable support 38 placed upon the ground. The pipe 35 is further provided at its outer end with squared portions 39. for engagement with a suitable sqiiare-soclreted wrench 40 designed to rotate the pipe section 85 and assembly attached thereto. its Will be seen in Figure 20. the boring operation is commenced with a full assembly and, after a partial boring. as shown in that tigure. the assembly is removed. the guide member 17 is detached. and a washer 27 inserted between the cutter 20 and the heads of the screws to prevent detachment of the cutter. after which the tool is reinserted and the boring continued. as shown in Figure 21.

"Hie herewithin method of boring is ex tremely efiicient and, as has been found in practice, the boring operation can be accomplished in one-halt of the time consumed by other methods. Because of the universal connection between the rotating and feed means and the tool. the boring operation can be performed when the axes thereof are/disaligned, thus permitting the operation of the apparatus under conditions which have heretofore been considered adverse.

The teeth of the cutter are What are known as left hand spiral cut and under the preferred method of re-boring, the cutter is of a dimension as to only make a finishing out, of say .010 from the normal diameter of the cylinder to be re-bored. Therefore, the pilot guide would be approximately .001 short of the normal cylinder diameter to allow it to slide within the cylinder, and the follower guide approximately .001 short of the cutter, so as to slide in the re-bored portion of the cylinder.

Therefore, my method of ire-boring a cylinder is to remove the metal to a depth of approximately .005 of an inch for each boring, and, if necessary. to successively bore the cylinder. removing .005 of an inch at each operation. until the re-finishing is suitably completed.

In Fig. 22 a series of different sized tools are illustrated in a progressive sized proportion. it, however, being obvious that the number of tools to a series may be varied according to the requirements of automobile engine cylinder reboring service. In said figure. tour sizes are disclosed.

The cylinderis re-bored by a step-by-step increase, each boring being a finishing boring. The follower guide of the cutter in one boring proportions may qualify as the pilot guide for the next successive boring, and while convenient it is desirable to provide a complete tool for each re-boring dimension: it is obvious and contemplated that the guide be interchangeable.

In the series shown in Fig. 22, a step-bystep increase of diameter between the suc cessive members of the guide pilot of each succeeding assembly is of equal diameter with the follower guide of the. preceding assembly. The guides a and a of tools m and mlare of equal diameter; guide i; has a diameter .010 of an inch greater than that of the diameter of a; guide 6' of tool :12 is equal in diameter to guide 6; guide 0 of tool a has a diameter .010 of an inch greater than the diameter of F2, and c of tool m is equal in diameter to c, this relation of pilot and follower guides to obtaining whatever the number of assemblies in a series.

The cutti deposited in the recesses 22, are removed through openings 22*, normally closed by threaded plugs 22, thus allowing for such removal without disassembly of the tool elements.

Having described my invention, 1 claim:

1. A- cylinder rte-boring tool, comprising a circular disk cutter having cutting teeth about its periphery, a cylindrical pilot member secured at one side of the cutter of a diameter corresponding to the normal diameter of the cylinder to be re-bored, and a cylindrical follower member secured at the opposite side of said cutter of a diameter approximating the cutting diameter of the cutter. said cutter and members connected together as a unit.

2. A cylinder re-boring' tool, comprisinga pair of cylinder members of difi'erent diameter concentrically engaged together, one member a pilot of a diameter corresponding to the normal diameter of the cylinder to be re-bored and the second of a diameter corresponding to the cylinder re-boring diameter of the cutter, a circular disk cutter coaxially secured between and to said members.

3. A cylinder re-boring tool comprising a cylindrical guide member having an annular recess in one end. and a circular disk cutter engaged over the recessed end of said guide member and rotatively connected therewith. the cutter having angular cutting teeth about its periphery with the spacing between the teeth open to said recess, said recess providing a. reservoir for collecting the cutter boring-s.

In witness whereof, I hereunto subscribe my name. as attested by the two subscribing witnesses.

VTCTUR G. HUWTND.

Witnesses:

ll. A. Bron, R. Krsrrmit. 

